KR20190122506A - polyketone film having controlable thermal shrinkage rate and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a polyketone film which can control the thermal shrinkage rate by adjusting the drawing temperature and drawing ratio, and a method for manufacturing the same.

Description

Polyketone film having controlable thermal shrinkage rate and manufacturing method

The present invention relates to a polyketone film used for packaging purposes, more specifically for food packaging purposes, and relates to a polyketone film capable of controlling heat shrinkage rate through a change in stretching conditions and a manufacturing method thereof.

Carbon monoxide and olefin copolymers are known as polyketones and can be used as raw materials for high strength fibers, food packaging and engineering plastics. In particular, polyketone is suitable for use in packaging films due to its superior impact resistance and abrasion resistance compared to other raw materials.

However, in the case of the conventional polyketone film, it was difficult to control the heat shrinkage rate so as to satisfy the heat shrinkage required in food packaging, etc., there was a problem that the process control is difficult.

Korean Patent Laid-Open No. 10-2017-0044336 (April 25, 2017) discloses that a polyketone is added to a polymer resin to prepare a high heat resistance and high barrier polyketone composite resin, and to apply it as a packaging material, a container, and a film. However, it still does not solve the problem of heat shrinkage control.

The present invention provides a heat shrinkage controllable polyketone which can control a heat shrinkage rate of a polyketone film used as a food packaging film to satisfy a suitable heat shrinkage rate required for each food packaging use, and further realize a high heat shrinkage rate of 10% or more. It is a problem to provide a film and its manufacturing method.

As a means for solving the above problem,

Polyketone film which can control the heat shrinkage rate of the present invention,

The stretching temperature is 20 to 80 ° C., and the stretching ratio is 2.5 to 3.5.

In addition, the polymerization temperature of the polyketone resin is characterized in that 70 to 90 ℃.

In addition, when the polyketone film is low viscosity, the heat shrinkage is characterized in that more than 10%.

In addition, when the polyketone film is high viscosity, the heat shrinkage is characterized in that more than 8%.

The manufacturing method of the polyketone film which can control the heat shrinkage rate of the present invention,

Preparing a polyketone resin by copolymerizing carbon monoxide, ethylene, and propene in the presence of a catalyst composition consisting of a palladium compound, an acid having a pKa of 6 or less, and a bipolar compound of phosphorus; Preparing a film with an extruder; And stretching the film; It includes, The stretching step is characterized in that the stretching temperature is 20 to 80 ℃, the stretching ratio is 2.5 to 3.5.

In addition, the polymerization temperature of the polyketone resin is characterized in that 70 to 90 ℃.

In addition, when the polyketone film is low viscosity, the heat shrinkage is characterized in that more than 10%.

In addition, when the polyketone film is high viscosity, the heat shrinkage is characterized in that more than 8%.

The polyketone film that can control the heat shrinkage rate of the present invention increases the heat shrinkage rate of the polyketone film under low temperature / high stretching conditions, decreases the heat shrinkage rate of the polyketone film under high temperature / low stretching conditions, and high viscosity to high viscosity under the same conditions. By controlling the heat shrinkage rate of the polyketone film by using the low heat shrinkage rate of the polyketone, the polyketone film has the effect of satisfying the appropriate heat shrinkage rate required for each packaging application, and furthermore, the high heat shrinkage rate of 10% or more can be realized. It has an excellent effect.

1 is a graph showing the results of measuring the thermal contraction rate of polyketone film for each stretching temperature at low viscosity and high viscosity.
Figure 2 is a graph showing the results of measuring the thermal shrinkage of the polyketone film for each draw ratio at low viscosity and high viscosity.

Hereinafter, the polyketone film which can control the thermal contraction rate of this invention, and its manufacturing method are demonstrated in detail.

The present invention relates to a polyketone film capable of controlling the thermal contraction rate, having a stretching temperature of 20 to 80 ° C and a stretching ratio of 2.5 to 3.5.

In addition, the present invention comprises the steps of preparing a polyketone resin by copolymerizing carbon monoxide, ethylene and propene in the presence of a catalyst composition consisting of a palladium compound, an acid having a pKa of 6 or less, and a ligand compound of phosphorus; Preparing a film with an extruder; And stretching the film; It includes, The stretching step relates to a method of producing a polyketone film capable of heat shrinkage controllable, characterized in that the stretching temperature is 20 to 80 ℃, the stretching ratio is 2.5 to 3.5.

The polyketone resin of the present invention is prepared by copolymerizing carbon monoxide and olefins.

The polyketone resin of the present invention is a linear alternating polyketone resin, a linear alternating structure comprising a ketone group and at least one ethylenically unsaturated hydrocarbon, and contains substantially one carbon monoxide per molecule of ethylenically unsaturated hydrocarbon. Suitable ethylenically unsaturated hydrocarbons for use as precursors of the polyketone resins of the present invention are ethylene, α-olefins (e.g. propene, 1-) having up to 20 carbon atoms, preferably up to 10 carbon atoms. Aliphatic hydrocarbons such as butene, isobutene, 1-hexene and 1-octene, or arylaliphatic hydrocarbons with aryl substituents on aliphatic molecules, in particular ethylene Arylaliphatic hydrocarbons having aryl substituents on unsaturated carbon atoms. Examples of the arylaliphatic hydrocarbons among the ethylenically unsaturated hydrocarbons include styrene, p-methyl styrene, p-ethyl styrene, m-isopropyl styrene, and the like. The ethylenically unsaturated hydrocarbons and the ketone compounds are copolymerized to form linear alternating polyketone resins, but among them, the linear alternating polyketones formed by copolymerizing ethylene and ketone compounds or at least three carbon atoms such as propene in the ethylene and ketone compounds The linear alternating polyketone formed by copolymerization of ethylenically unsaturated hydrocarbons is preferred in view of easy copolymerization reaction and relatively uniform molecular weight of the copolymerized linear alternating polyketone. Preferred polyketone resins are copolymers of carbon monoxide and ethylene, more preferably linear terpolymers of carbon monoxide, ethylene and propene.

When the polyketone resin is a linear alternating polyketone terpolymer, the molar ratio of ethylene and propene is preferably 43: 7 to 46: 4.

Propene can adjust the melting point (Tm), the higher the content of the propene has the effect of lowering the Tm. When ethylene and propene are in the molar ratio range, Tm is easy to extrude because it is in the range of 190 to 220 ° C.

If the melting point is less than 190 ℃ (7% or more propene), the polymerization is difficult, the physical properties such as mechanical properties and barrier properties are deteriorated, the melting point is more than 220 ℃ (propene is 4% or less In the case of) extrusion temperature is usually higher than the melting point 20 ℃ 240 ℃ or more, polyketone is thermal decomposition at 240 ℃ or more, there is a problem that the extrusion processing is impossible.

As a method for producing a polyketone resin, a method of liquid-polymerizing carbon monoxide and olefins using an alcohol solvent in the presence of a catalyst composition consisting of a palladium compound, an acid having a pKa of 6 or less, and a ligand compound of phosphorus may be employed.

As the palladium compound, palladium acetate is preferable. Specific examples of the acid having a pKa value of 6 or less include trifluoroacetic acid, p-toluenesulfonic acid, sulfuric acid, sulfonic acid, and the like. Dimethyl-1,3-dioxane-5,5-diyl) bis (methylene)) bis (bis (2-methoxyphenyl) phosphine) is preferred. At this time, the palladium compound and the acid content of pKa 6 or less is preferably 1:10 molar ratio.

The polyketone resin of the present invention performs a polymerization reaction at 70 to 90 ℃. If the polymerization temperature is less than 70 ℃ viscosity is too high impossible extrusion process, if it is more than 90 ℃ viscosity is too low when melt-strength (molt-strength) during film formation after extrusion is difficult to form the film.

In the present invention, when the polymerization temperature is 70 ℃ MI (Melt Index) is a high viscosity of 2 to 4, when the polymerization temperature is 90 ℃ MI is a low viscosity of 20 to 40. At this time, the higher the temperature in the polymerization temperature range, the molecular weight and viscosity are reduced to control the low viscosity and high viscosity.

The polyketone resin is prepared in pellet form using a screw, then made into a film on a film extruder, and then stretched.

It is preferable that the extending | stretching temperature in the extending process of a polyketone film is 20-80 degreeC. When the temperature is less than 20 ° C., the film is hard and requires a lot of force to be stretched, and thus it is difficult to be stretched by a general stretching equipment.

It is preferable that a draw ratio in the extending process of a polyketone film is 2.5-3.5. If it is less than 2.5 has a heat shrinkage of less than 8% to reach a high heat shrinkage rate, if it is more than 3.5 the film is broken and it is impossible to stretch.

The polyketone film of the present invention may have a high heat shrinkage rate when the stretching process is performed at the stretching temperature and the stretching ratio. More specifically, in the case of low viscosity, the heat shrinkage rate may be 10% or more, and in the case of high viscosity, the heat shrinkage rate may be 8% or more.

Hereinafter, the present invention will be described in detail through specific examples and comparative examples, and these examples are only to illustrate the present invention and should not be construed as limiting the scope of the present invention.

The method of measuring the heat shrinkage rate of the polyketone film shown in Examples and Comparative Examples described below is as follows.

Heat shrinkage  How to measure

The polyketone film was stretched in the longitudinal direction at a temperature controllable UTM (Universal Testing Machine) with drawing temperature and draw ratio according to each example and comparative example to perform evaluation under heat shrinkage conditions (dry oven, 150 ° C., 30 seconds). It was.

Example  One

Linear alternating polyketone terpolymers consisting of carbon monoxide, ethylene and propene include palladium acetate, trifluoroacetic acid and ((2,2-dimethyl-1,3-dioxane-5,5-diyl) bis (methylene)) bis ( Prepared in the presence of a catalyst composition produced from bis (2-methoxyphenyl) phosphine). In the above, the content of trifluoroacetic acid relative to palladium is a molar ratio of 10 times, and goes through a first stage of polymerization temperature 70 ℃ and two stages of 80 ℃. The molar ratio of ethylene and propene in the polyketone terpolymer prepared above was 45 to 5. In addition, the melting point of the polyketone terpolymer is produced in two types of high viscosity / low viscosity type of 200 ℃, measured by HFIP (hexa-fluoroisopropano) at 25 ℃ LVN (intrinsic viscosity) high viscosity 2.4dl / g, low viscosity 1.6 dl / g, MI (Melt index) was 3g / 10min of high viscosity, and 30g / 10min of low viscosity. The two polyketone terpolymers prepared above were 40 mm in diameter operating at 250 rpm, and were manufactured as pellets on an extruder using a biaxial screw with L / D = 32, and 30 mm in diameter operating at 100 rpm. A 100 micron thick film was produced on a film extruder with hot / cold control using a single screw with L / D = 30. Thereafter, in the stretching step, the stretching temperature of the film is 20 ° C., and stretching is performed three times in the longitudinal direction.

Example  2

Except that the stretching temperature of the film in Example 1 is 50 ℃ was prepared in the same manner as in Example 1.

Example  3

Except that the stretching temperature of the film in Example 1 is 80 ℃ was prepared in the same manner as in Example 1.

Example  4

Except that the stretching temperature of the film in Example 1 is 50 ℃, the film is stretched 2.5 times in the longitudinal direction is prepared in the same manner as in Example 1.

Example  5

In Example 1, the stretching temperature of the film was prepared in the same manner as in Example 1 except that the film was stretched 50 times in the longitudinal direction at 50 ° C.

Comparative example  One

Except that the stretching temperature of the film in Example 1 is 120 ℃ was prepared in the same manner as in Example 1.

Comparative example  2

Except that the stretching temperature of the film in Example 1 is 50 ℃, the film was stretched 2.0 times in the longitudinal direction is prepared in the same manner as in Example 1.

Thermal contraction rate (%)-draw ratio according to drawing temperature of polyketone film is fixed at 3.0 Example 1 Example 2 Example 3 Comparative Example 1 Low Viscosity Heat Shrinkage 16 14 11 3 High Viscosity Heat Shrinkage 13 12 9 2

Thermal contraction rate (%) according to draw ratio of polyketone film-draw temperature is fixed at 50 ℃ Example 2 Example 4 Example 5 Comparative Example 2 Low Viscosity Heat Shrinkage 12 11 14 10 High Viscosity Heat Shrinkage 11 8 13 7

Claims (8)

A stretching temperature is 20 to 80 ℃, the stretching ratio is 2.5 to 3.5 characterized in that the heat shrinkage controllable polyketone film. The polyketone film of claim 1, wherein the polymerization temperature of the polyketone resin is 70 to 90 ° C. The polyketone film of claim 1, wherein the heat shrinkage rate is 10% or more when the polyketone film has a low viscosity. The polyketone film of claim 1, wherein the heat shrinkage rate is 8% or more when the polyketone film has a high viscosity. Preparing a polyketone resin by copolymerizing carbon monoxide, ethylene, and propene in the presence of a catalyst composition consisting of a palladium compound, an acid having a pKa of 6 or less, and a bipolar compound of phosphorus; Preparing a film with an extruder; And stretching the film; Including the stretching step, the stretching temperature is 20 to 80 ℃, the draw ratio is 2.5 to 3.5, the method of manufacturing a polyketone film controllable heat shrinkage, characterized in that. The method for producing a polyketone film according to claim 5, wherein the polymerization temperature of the polyketone resin is 70 to 90 ° C. The method of claim 5, wherein the heat shrinkage is 10% or more when the polyketone film is low viscosity. The method of claim 5, wherein the heat shrinkage is 8% or more when the polyketone film is high viscosity.

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